The company, which owns Paradisepoker.com, has app-roached several agencies and is holding pitches this week.
Once appointed, the successful agency will take on responsibility for revamping the brand using print, press, online and direct marketing.
In the past, the gaming company, which currently spends £20 million on its European advertising, has produced much of its communications in-house. Last year, Astroman, a Polish agency, produced a poster and print campaign for Paradisepoker.com featuring the model Caprice.
The pitch does not affect Sportingbet's relationship with the BD Network and Pacific Media Worldwide, which handle European sales promotions and media planning respectively.
Robert Boatwright-Smith, the head of promotions at Sportingbet, said: "We're looking for a pan-European marketing agency so we can speak with a singular voice."